A head-mounted device includes a housing, a mask, and an optical machine assembly. An accommodating chamber is formed in the housing. The upper portion of the mask is connected to the housing, and the lower portion of the mask exceeds out of the housing. The optical machine assembly comprises: an optical machine support arranged in the accommodating chamber; an optical machine, positioned in the accommodating chamber; a waveguide piece; a connecting body, positioned in the accommodating chamber, the optical machine and the waveguide piece being mounted on the connecting body, and the connecting body being fixed to the optical machine support. The waveguide piece penetrates through the bottom of the housing from the accommodating chamber and extends downwards.